Non-Invasive Fibrosis Testing in Adults With Obesity and MASLD: A Systematic Review and Meta-Analysis.

AIMS: Adults with obesity are at increased risk of metabolic dysfunction-associated steatotic liver disease (MASLD)-related fibrosis, but the diagnostic performance of non-invasive tests (NITs) in this population remains uncertain. This meta-analysis evaluated NITs for detecting significant (≥F2) and advanced (≥F3) fibrosis in adults with obesity and MASLD. MATERIALS AND METHODS: PubMed/MEDLINE, Embase, Web of Science and the Cochrane Library were searched from inception to 1 December 2025. Eligible studies enrolled adults with obesity (BMI ≥ 30 kg/m2) and MASLD, compared an NIT with liver biopsy, and provided data to estimate sensitivity and specificity. Pooled estimates were derived using bivariate random-effects models; HSROC curves were generated for each test and fibrosis threshold. RESULTS: Twenty-seven studies including 5034 participants were included. Mean age was 40.6 ± 11.4 years and mean BMI was 43.3 ± 7.1 kg/m2. For significant fibrosis (≥F2), vibration-controlled transient elastography (VCTE) showed a sensitivity of 0.64 (95% CI, 0.49-0.77) and specificity of 0.77 (95% CI, 0.66-0.85), with a median threshold of 7.95 kPa (IQR, 7.60-12.00). FIB-4 showed broadly comparable performance, with a sensitivity of 0.65 (95% CI, 0.53-0.75) and specificity of 0.77 (95% CI, 0.64-0.86). For advanced fibrosis (≥F3), VCTE showed a sensitivity of 0.77 (95% CI, 0.67-0.85) and specificity of 0.84 (95% CI, 0.76-0.90), with a median threshold of 10.73 kPa (IQR, 8.15-12.80). Serum-based tests showed more variable operating characteristics. Post hoc threshold analyses showed the expected trade-off between sensitivity and specificity at lower VCTE cut-offs. CONCLUSIONS: In adults with obesity and MASLD, VCTE showed the most consistent diagnostic performance, particularly for advanced fibrosis, whereas serum-based tests demonstrated more variable operating characteristics. Threshold selection and technical feasibility remain important determinants of performance, highlighting the need for validated obesity-specific thresholds and diagnostic pathways.